The present invention relates to an information storage and retrieval device which prevents damage to the mechanism inside the device when the device is exposed to some type of shock. More particularly, this invention is applied to small magnetic disk drives such as 2.5 inch, 1.8 inch, 1.3 inch, or other disk drives yet to be developed.
A small magnetic disk drive of the prior art is described in unexamined Japanese patent publication 6-96532. According to this publication, stacked recording disks are rotated with a constant velocity by a disk rotating motor which is fixed to a base. Heads are supported by supporting springs to a carriage, and float on the disks with a minute gap, and record and reproduce information. A voice coil motor rotatively drives the carriage and precisely positions the heads with high speed. The carriage is supported to a pivot assembly consisting of a sleeve with a shaft and two ball bearings and is fixed to the base, so that the carriage can rotate around the shaft.
The voice coil motor which drives the carriage includes a driving coil, permanent magnet, and yoke. The driving coil is fixed to the carriage and the permanent magnet and yoke (referred to as xe2x80x9cmagnet yoke assemblyxe2x80x9d) are fixed to the base. The driving coil is placed in a magnetic field and magnetically affected so that with an electric current flowing through the driving coil drives the carriage to position the heads as desired.
Recently, such devices are becoming smaller and thinner and the market for removable and portable pocket-sized devices like IC cards is growing. Therefore, a durable device is required to bear the shock and prevent any damage from occurring to the device even when it is bumped or dropped to the floor. There are two ways to improve the durability. One is to improve the durability of each individual element inside the device such as positioning mechanism, disks, and slider, etc. Another way is to protect the whole device from shock.
An example of protecting the whole device from shock is disclosed in unexamined Japanese patent publication 1-311495. In this example, vibration and shock-absorbing materials are arranged on all four sides of the device and the device body is mounted to the inner case by the vibration and shock-absorbing materials. The inner case is provided with projected guides and is removably stored in a case having a guide rail. This way, the vibration and shock transmitted to the device body is reduced.
Another example is disclosed in unexamined Japanese patent publication 4-368690.In this example, chloroprene rubber shock-absorbing materials are arranged at the four corners of the magnetic disk drive housing, thereby protecting the inner mechanism of the device from damage.
Rubber shock-absorbing materials are utilized in the above described examples to prevent damage to the mechanism in the housing. However, when a device is dropped to the floor by mistake, the shock to the device is enormous and arranging rubber shock-absorbing material at a part of the device as disclosed above may not be sufficient to absorb the shock.
Additionally, the relation of the dimensions of the device and the combined device are not adequately taken into consideration. Therefore, when the conventional method is applied to a removable device, for example a card type, etc., there may be a size problem in that the combined device cannot be mounted in a standard bay of an information processing device.
A main purpose of the present invention is to provide an information storage and retrieval device provided with a shock-absorbing mechanism which can absorb shock energy well enough to prevent damage to the mechanism inside the device even when the device is dropped to the floor by mistake. It is also a purpose of the present invention to provide an information storage and retrieval device that is capable of being installed in a standard-sized bay of an information processing device. Preferably, the shock-absorbing material which is composed with a mixture of solid particles and viscous elastic material is arranged at the periphery of the housing. Also, after a shock, the shock-absorbing material will be deformed and may or may not return to its original shape by itself.
Furthermore, the amount of the shock acceleration given to the device is roughly obtained by comparing the deformed shape of the shock-absorbing material with a quick comparison table. This table is created by measuring the deformed shape of the shock-absorbing material with respect to different shock acceleration values applied to the device.
The whole device is mounted in a shock-absorbing case, and the thickness of the part of the shock-absorbing case which contacts the side of the device is thicker than the part which contacts the cover and base of the device. The shock-absorbing case is preferably made of shock-absorbing material having a mixture of solid particles and viscous elastic material or rubber or plastics. The surface of the shock-absorbing material may be coated with viscous elastic material which is harder than the viscous elastic material which forms the shock-absorbing material. Spring or fiber-net material may used as a mixture with the viscous elastic material to form the shock-absorbing material instead of solid particles.
The original shape of the shock-absorbing material is easily restored manually after the deformation, and the shock-absorbing material can be used repeatedly.
The shock-absorbing material is arranged to be within the form factor dimension of small magnetic disk drives.
The shock-absorbing case in which the device is mounted and or shock-absorbing material may be made from transparent material, so that the information storage and retrieval device can be seen from outside.
In order to achieve the above described purposes of the present invention, as well as others not specifically mentioned, the present invention provides a combined information storage and retrieval device having an information storage and retrieval device, which has a nearly rectangular shape, and which conforms to one specific standard among a series of standards for the dimensions of magnetic disk drives. A shock-absorbing material is provided enclosing the outside of the device along with some means to connect the shock-absorbing material with the device. The combined information storage and retrieval device conforms to a dimensional standard one or two standard sizes larger than that of device alone.
To conform with the requirements of the dimensional standard of the larger combined device, an input-output connector of the prescribed type is provided at the prescribed location and is connected to the input-output connector of the smaller device inside. This way, the combined device is used as an information storage and retrieval device of a larger dimensional standard.
Preferably, the height of the shock-absorbing material is arranged to be nearly the same as the height of the device. The shock-absorbing material is separated into two parts, an upper part and lower part, and a plurality of projections are formed on the facing surfaces of the two parts. The two parts are frame-shaped and are engaged with each other with the projections and form a united shock-absorbing component. The connecting means is preferably composed of adhesive layers on both the top and the bottom of the combination of the device and the shock-absorbing material, and metal plates which are attached to the combination to form the combined device. The metal plates are preferably provided with small holes to radiate heat from the device. The width and length of the metal plates are arranged to be larger than those of the device and smaller than those of the shock-absorbing material.
These and other objects, features and advantages of the present invention will become more apparent in view of the following detailed description of the present invention in conjunction with the drawings.